The invention relates to a cartridge with a plurality of C-shaped ligature clips, with a housing accommodating ligature clips arranged in a row one behind the other and parallel to one another, with a transport element, which can be slid forward and back relative to the housing in the direction of the row and which when sliding forward and back relative to the housing causes at least one ligature clip to advance towards a discharge end of the cartridge.
Cartridges of this type are used in instruments, with which ligature clips can be placed against a vessel of the body in order to thus ligate the vessel. Such ligature clips are known in a wide variety of types and substantially consist of a C-shaped body with a bridge section and two legs that can be bent towards one another so that they constrict and clamp a section of a vessel between them.
In the case of known instruments of this type the ligature clips are arranged in a row one behind the other so that the legs run substantially parallel to the direction of advance of the ligature clips in the cartridge and point towards the discharge end of the cartridge with their free ends. The C-shaped ligature clips are advanced stepwise in the cartridge in the direction of the discharge end by a transport element. The respective ligature clip furthest forward is then slid in between two tools configured as clamping jaws, which compress the ligature clip after placement on the vessel section to be closed and thus secure it permanently on the vessel section. It is known in this case to alternately slide the transport element forward and back relative to the housing, wherein on each such step comprising sliding forward and back the ligature clips are respectively advanced by one position in the cartridge in the direction of the discharge end (DE 44 29 084 C1; EP 1 198 204 B1; DE 196 03 889 C2).
In known cartridges of this type the transport element is arranged in one plane next to the plane in which the ligature clips are located, so that the transport elements must be relatively stable in configuration to be able to absorb the bending moments that thus occur. Moreover, space is required beside the ligature clips, in which the transport element can be accommodated. In known cartridges both the transport element and the ligature clips must have their own guide means in the housing that assure precise relative movement and prevent a jam from occurring or prevent the transport elements from being deformed.
Cartridges are also known, in which the ligature clips located one behind the other are supported against one another so that all the ligature clips are advanced together in the cartridge by a feed element that acts on the ligature clip furthest to the rear. However, this requires that the consecutive ligature clips are supported against one another and a disadvantage with these designs is that production tolerances of the ligature clips accumulate and that substantial feeding forces must be transmitted by means of the feed element and in particular the ligature clips lying at the back (DE 695 25 083 T2).
It is necessary especially for minimally invasive surgery to provide placement tools for ligature clips that have the smallest possible dimensions, e.g. an elongate barrel with the smallest possible diameter. It is thus extraordinarily difficult to arrange a cartridge for ligature clips inside the available space and, moreover, the at least one transport element necessary for advancing the ligature clips.
It is an object of the invention to configure a cartridge of the above type so that a reliable advancing function of the ligature clips in the cartridge can be assured with the lowest possible design expenditure and small structural size.